In turbochargers where the turbine speed ranges from 100,000 rpm to 110,000 rpm, labyrinth-type seals are frequently utilized so as to minimize bearing and seal wear. Such seals, while effective when the turbine and compressor wheels are operating at normal high speeds, nevertheless are plagued with the problem of lubricant migration into the compressor chamber when rotation of the wheels is stopped or is at idling speed. To compensate for the dilemma, various means have heretofore been provided which were beset with one or more of the following shortcomings: (a) complex and costly construction and prone to frequent malfunction; (b) resulted in increased oil consumption and carbonizing of various components of both the engine and turbocharger; and (c) could not be readily installed in existing turbochargers without requiring extensive modifications to the various components of the turbocharger.